The SPT drive rod are manufactured to connect with the SPT split tube sampler and comply with the BS 1377: Part 9: 1990.
The Rod OD is 54mm with solid 1-1/2" BS whitworth make and female tool joints on each end, Tool joints are friction welded to the rods and have a pair of spanner flats to facilitate handing.
The Automatic Trip Hammer is designed for carrying out the Standard penetration Test (SPT) to BS 1377: Part 9: 1990. SPT Drive Rods and a split Tube Sampler are connected to base of the anvil, and driven into the ground by the falling weight.
The hammer comprises a drop weight of 63.5 kg and a pick-up and selftripping mechanism that ensures the weight has a free fall of exactly 760mm.
The inner shaft acts as a guide on which the weight drops with minimal resistance and strikes the anvil squarely.
The trip hammer is supplied with a Safety retaining bolt to prevent the weight from sliding when the hammer is not in use or during transport.